Multiple lamination high density interconnect process and structure

Claim 2

The high density interconnect structure recited in claim 1 further comprising: a thermoplastic release layer disposed between said second lower sublayer and said first metallization and first dielectric layers.

Claim 3

The high density interconnect structure recited in claim 1 wherein: said second layer of dielectric material has via holes therein disposed in alignment with some of said contact pads and/or portions of said first metallization layer; and said high density interconnect structure further comprises: a patterned second metallization layer disposed on said second layer of dielectric material and extending into contact with selected contact pads and/or selected portions of said first metallization layer in said via holes in said second layer of dielectric material.

Claim 4

The high density interconnect structure recited in claim 3 further comprising: a third layer of dielectric material bonded to said second metallization layer and exposed portions of said second layer of dielectric material, said third layer of dielectric material comprising third lower and third upper sublayers, said third lower sublayer being a thermosetting polymer which can be cured at a temperature which is lower than T g1 , said third upper sublayer being stable over a range of temperatures above the minimum curing temperature of said thermosetting polymer.

Claim 5

The high density interconnect structure recited in claim 4 wherein: said third layer of dielectric material has via holes therein disposed in alignment with some of said contact pads and/or portions of said first metallization layer and/or portions of said second metallization layer; and said high density interconnect structure further comprises: a patterned third metallization layer disposed on said third layer of dielectric arterial and extending into contact with selected contact pads and/or selected portions of said first metallization layer and/or portions of said second metallization layer in said via holes in said third layer of dielectric material.

Claim 6

The high density interconnect structure recited in claim 1 wherein: said second layer of dielectric material has via holes therein disposed in alignment with at least some portions of said first metallization layer; and said high density interconnect structure further comprises: a patterned second metallization layer disposed on said second layer of dielectric material and extending into contact with at least some portions of said first metallization layer in said via holes in said second layer of dielectric material.

Claim 7

The high density interconnect structure recited in claim 1 wherein: said first and second upper sublayers are thermoset polymers.

Claim 8

The high density interconnect structure recited in claim 7 wherein: said first and second upper sublayers are thermoset polyimide.

Claim 9

The high density interconnect structure recited in claim 7 wherein: said first lower sublayer comprises polyetherimide; and said second lower sublayer comprises a siloxane-polyimide/epoxy copolymer blend.

Claim 10

The high density interconnect structure recited in claim 1 further comprising: a second high density interconnect structure; an overall high density interconnect structure bonded to said second high density interconnect structure and the first recited high density interconnect structure, said overall high density interconnect structure comprising a first overall dielectric layer laminated to said first and second high density interconnect structures, said first overall dielectric layer having via holes therein in alignment with selected conductors of said first and second high density interconnect structure and a first overall metallization layer disposed on said first overall dielectric layer and extending into said via holes into electrical contact with selected ones of the conductors of said first and second high density interconnect structures.

Claim 11

The high density interconnect structure recited in claim 1 wherein: at least one of said upper sublayers is thermoplastic.

Claim 12

The high density interconnect structure recited in claim 11 wherein: said first and second upper sublayers are thermoplastic.

Claim 13

In a method of fabricating a high density interconnected system of the type including a plurality of electronic chips, a high density interconnect structure including a layer of dielectric material bonded to said chips and a pattern of conductors disposed on or in said dielectric material, the conductors of said high density interconnect structure electrically interconnecting said electronic chips, the improvement comprising: a) providing a basic structure comprising said electronic chips, a first dielectric layer bonded to said chips, said first dielectric layer having a plurality of via holes therein and a patterned first metallization layer disposed thereon, said first metallization layer including conductors which extend into ohmic contact with contact pads in said via holes; b) disposing a release layer in said via holes over said first metatlization layer; and c) laminating a second dielectric layer over said release layer using a crosslinking polymer adhesive which can be cured at a temperature at which said basic structure is stable, said second upper sublayer being stable over a range of temperatures above the minimum curing temperature of said crosslinking polymer, this laminating step being performed at a low enough temperature that said first dielectric layer remains fixed, whereby said first metallization layer and its contacts to said contact pads are not adversely affected by this laminating step.

Claim 14

The improvement recited in claim 13 further comprising the steps of: d) forming second layer via holes in said second dielectric layer and said second adhesive in alignment with said contact pads and/or said first metallization layer; and e) forming a patterned second metallization layer on said second dielectric layer, said second metallization layer including conductors which extend into ohmic contact with conductors of said first metallization layer and/or said contact pads in said second layer via holes.

Claim 15

The improvement recited in claim 14 further comprising the step of: f) laminating a third dielectric layer to said second metallization layer and exposed portions of said second dielectric layer using a third thermosetting polymer which can be cured at a temperature which is lower than T g1 , said third upper sublayer being stable over a range of temperatures above the minimum curing temperature of said thermosetting polymer, this laminating step being performed at a low enough temperature that said first and second dielectric layers remain fixed, whereby said second metallization layer and its contacts to said contact pads and/or said first metallization layer are not adversely affected by this laminating step and said first metallization layer and its contacts to said contact pads are not adversely affected by this laminating step.

Claim 16

In a method of fabricating a high density interconnected system of the type including a plurality of electronic chips, a high density interconnect structure including a layer of dielectric material bonded to said chips and a pattern of conductors disposed on or in said dielectric material, the conductors of said high density interconnect structure electrically interconnecting said electronic chips, the improvement comprising: a) laminating a first dielectric layer to said chips using a first thermoplastic adhesive having a first glass transition temperature T g1 ; b) forming via holes in said first dielectric layer and said first adhesive in alignment with at least some contact pads of said chips; c) forming a patterned first metallization layer on said first dielectric layer, said first metallization layer including conductors which extend into ohmic contact with contact pads in said via holes; d) disposing a release layer in said via holes over said first metallization layer; e) laminating a second dielectric layer over said release layer using a crosslinking polymer adhesive which can be cured at a temperature at which said basic structure is stable, said second upper sublayer being stable over a range of temperatures above the minimum curing temperature of said thermosetting polymer, this laminating step being performed at a low enough temperature that said first dielectric layer remains fixed, whereby said first metallization layer and its contacts to said contact pads are not adversely affected by this laminating step.

Claim 17

The improvement recited in claim 14 further comprising the steps of: f) forming second layer via holes in said second dielectric layer and said second adhesive in alignment with said contact pads and/or said first metallization layer; and g) forming a patterned second metallization layer on said second dielectric layer, said second metallization layer including conductors which extend into ohmic contact with conductors of said first metallization layer and/or said contact pads in said second layer via holes.

Claim 18

The improvement recited in claim 17 further comprising the step of: h) laminating a third dielectric layer to said second metallization layer and exposed portions of said second dielectric layer using a third thermosetting polymer which can be cured at a temperature which is lower than T g1 , said third upper sublayer being stable over a range of temperatures above the minimum curing temperature of said thermosetting polymer, this laminating step being performed at a low enough temperature that said first and second dielectric layers remain fixed, whereby said second metallization layer and its contacts to said contact pads and/or said first metallization layer are not adversely affected by this laminating step and said first metallization layer and its contacts to said contact pads are not adversely affected by this laminating step.

Claim 19

The improvement recited in claim 16 wherein said laminating step comprises: forming a layer of said crosslinking adhesive over said release layer; drying said layer of crosslinking adhesive; laminating a preformed film of dielectric arterial to said structure using said crosslinking adhesive as the adhesive for that film.

Claim 20

A printed circuit board comprising: a first thermoset dielectric film; a first metallization layer disposed on said first thermoset dielectric film; a second thermoset dielectric film bonded to said first metallization layer and said first thermoset dielectric film by a SPI/epoxy crosslinking copolymer blend.